A wide area network (WAN) is also called a remote network, which generally crosses a very large physical range and has a coverage range from dozens of kilometers to thousands of kilometers. A wide area network can connect multiple cities or countries or stretch across several continents, and can provide long-distance communication, to form an international remote network.
A local area network (LAN) refers to a computer communication network that is formed by interconnecting various computers, external devices, and databases in a local geographical range (for example, in a school, a factory, and an institution). A local area network can be connected to a distant local area network, database, or processing center by using a data communication network or a dedicated data circuit, to form an information processing system that covers a large range.
With development of communications technologies, a mobile network access device which includes a Second Generation (2G)/Third Generation (3G)/Fourth Generation (4G) module and a Wireless Fidelity (WiFi) module, supports wired network data transmission, and has a wireless access device (for example, access point (AP)) hotspot function, can access a wireless wide area network by using the 2G/3G/4G module, and establish a wireless local area network by using the WiFi module, so that another network accesses device accesses the wireless local area network to access the Internet. In this process, as a network node, the mobile network access device implements a connection between the wide area network and the local area network. The mobile network access device may be: a mobile phone, a wireless router, a tablet, or the like.
In a process of implementing the network access, the inventor discovers that the prior art has at least the following problem: due to reasons such as production cost and product size, the mobile network access device does not have a wired access function, and cannot access a wired wide area network by means of a wired network.